Factsheet n째 13
Environmental product declaration (EPD) (Version December 2010) EPD FOR POLYURETHANE INSULATION BOARDS AND ENERGY SAVING POTENTIAL What is an Environmental Product Declaration? An environmental product declaration, EPD, is a communication tool that provides quantified information of the potential environmental impacts of a product or process based on information from a life cycle assessment (LCA) over its entire lifetime or a part of it. EPDs are not providing an evaluation of the environmental performance but are a comprehensive and transparent set of environmental information covering a predefined set of life cycle stages. An important advantage of using EPD is the possibility to add LCA-based information in the supply chain. This feature makes EPDs particularly valuable for the building sector where the final building is based on a large number of materials, construction products, semi-manufactured products and processes.
What is PU? PU insulation stands for a group of insulation materials based on PUR (polyurethane) or PIR (polyisocyanurate). Their closed cell structure and high cross-linking density give them the characteristics of good heat stability, high compressive strength and excellent insulation properties. PU insulation has a very low thermal conductivity, starting from as low as 0.022 W/mK, making it one of the most effective insulants available today for a wide range of applications.
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PU Europe calculation tool Given the increasing number of national schemes and the ongoing development of a European standard for the establishment of EPDs (prEN 15804), PU Europe1 decided to develop an industrybased calculation programme based on the future pan-European standardised approach prepared by CEN/TC 350. The PU Europe tool is a third party verified system to produce cradle-to-gate construction product EPDs. A sensitivity analysis has demonstrated that modifications in the composition of the foam and the energy consumption of the foam production stage have no significant impact on the EPD results and therefore industry average data can be recommended for use in building assessments. However, the calculation tool allows PU Europe member companies to produce their own EPD and share them in their business-to-business communication channel where relevant. It must be made clear, throughout the communication chain, that EPDs cannot be compared with each other and that only an assessment at the building level, in a given end-use application, is relevant. Furthermore, LCA practitioners generally use the rule of thumb that the error margins for primary energy use and global warming potential can be estimated at around 10 %, whereas a 20 % error margin usually applies for all other impact categories. This means that any differences between these margins should be considered as insignificant.
PU EUROPE excellence in insulation - Factsheet n째 13
Factsheet n째 13
The PU Europe EPD tool has been jointly developed by PE International (Germany) and the UK-based Building Research Establishment (BRE). It is linked to the Gabi software tool and database. Details on the background information and model can be obtained by contacting PU Europe office. The results apply for both PUR and PIR insulation boards. The PU Europe tool will be adapted when required to reflect modifications in the draft European standard.
Updating of the EPDs for polyurethane (PU) insulation boards PU manufacturers and raw material suppliers are committed to continuously improve the
environmental performance of PU insulation and provide relevant environmental data. Since no industry data were available for the first version of factsheet 13, the environmental impact of the polyester polyols, which account for about 20-30 % of all PU, was based on surrogate data developed by PE International. This first revision takes account of a recent industry average life cycle inventory study for polyester polyols2. With these new and more representative figures, the overall environmental impact of PU insulation boards is lower in all impact categories than calculated in version 1 of factsheet 13. As a matter of example, the global warming potential of polyols was reduced by as much as 43 % leading to a 14.6 % lower GWP for insulation boards without facings (naked foam). A revision of the eco-profile for MDI (55-65 % of raw materials) is under way leading to a second revision of this factsheet planned in 2011.
Reduction of the environmental impact of 1 kg naked foam thanks to lower burdens from the polyols (without energy recovery)
* can be rounded to zero
PU EUROPE excellence in insulation - Factsheet n째 13
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Factsheet n째 13
Average European cradle-togate EPDs for polyurethane (PU) insulation boards Polyurethane insulation boards have the particularity to be supplied with various types of facings depending on the type of application and the required insulation performance3. This factsheet provides several sets of EPDs: a set for the naked polyurethane foam at two basic reference units: 1 kg foam and 1 m2 at a thermal
resistance value of R=1. Another set of four EPDs for insulation boards with a thermal resistance of R=5 and with different facings is also provided. With a view to further increasing the value of our EPD, this updated factsheet distinguishes between a cradle-to-gate scenario and a scenario including end-of-life (energy recovery). The inclusion of energy recovery in the EPD leads to a significantly lower total primary energy use (68.6 MJ instead of 85.5 MJ per kg of naked foam), but increases the global warming potential from 3.8 kg CO2 to 5.8 kg CO2.
Reference units: 1 kg and thermal resistance R = 1 m2K/W
* can be rounded to zero GWP Global warming potential ODP Ozone depletion potential AP Acidification potential
EP Eutrophication potential POCP Photochemical ozone creation potential
PU EUROPE excellence in insulation - Factsheet n째 13
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Factsheet n° 13
Reference unit: thermal resistance of R = 5 Wm2K
* can be rounded to zero
The importance of the functional or reference units It is important to take into account the density and thickness of any insulation material used in a particular end-use application. These two parameters will determine the overall quantity of a specific insulant required for that application as well as its related environmental impacts. Comparative assertion at the building or component levels have also to consider the required performance and the possible need to add ancillary materials to achieve comparable building component performance. For insulation products, there are two useful types of functional or reference units:  Those based on the thermal resistance performance, e.g. 1 m2 of a wall element at a
PU EUROPE excellence in insulation - Factsheet n° 13
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Factsheet n° 13
fixed R-value (or U-value). In this case, the use phase impacts related to energy consumption could be considered equivalent for the different solutions studied.
This also means that the amount of energy used to produce PU insulation is subsequently recovered in about half a year thanks to the energy saved in use phase.
Those based on the thickness of the insulant, e.g, 1 m2 of a wall element with 5 cm of insulation. This reference unit is especially relevant in renovation projects, where the difference in insulation thickness may result in different thermal performance levels of the building element and therefore a different use phase energy consumption and related environmental impacts. For additional support as to how to use EPD data please contact PU Europe.
Insulation and energy saving potential calculation EPDs provide a series of relevant information for use at different levels of the performance assessment. This chapter offers an assessment of the potential savings that polyurethane insulation can achieve over its life cycle. The graph shows that with only 120 mm of PU insulation, which is equivalent to an R-value of 5, annual energy savings of 217 kWh of primary energy per m2 insulated surface can be achieved. Over a 50 years lifetime, the savings will sum up to 10,850 kWh per m2, while only 100 kWh (or 356 MJ as calculated by the EPD) will be used to produce the 1 m2 of board in the first place, a 1 to 110 ratio. If energy recovery as end-of-life scenario is included in the calculation, then the primary energy use for 1 m2 of board would be reduced to 81 kWh (288.7 MJ). Under this scenario, the PU insulation would save 134 times the energy used for its production.
DISCLAIMER While all the information and recommendations in this publication are to the best of our knowledge, information and belief accurate at the date of publication, nothing herein is to be construed as a warranty, express or otherwise.
Notes [1] PU Europe is the European association of PU insulation manufacturers (www.pu-europe.eu) [2] See http://www.pu-europe.eu/site/fileadmin/Reports_public/PU_10-204_PU_Europe_project_-_EcoProfile_of_Aromatic_Polyester_Polyols__APP_.pdf [3] For more details see website www.excellence-in-insulation.eu
PU EUROPE excellence in insulation - Factsheet n° 13
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